Regulators: Nuclear plant leak didn’t require notice
Minnesota regulators knew four months ago that radioactive waste had leaked from a nuclear power plant in Monticello – but they didn’t announce anything about the leak until last week.
The delay in notifying the public about the November leak raised questions about public safety and transparency, but industry experts said Friday there was never a public health threat. They said Xcel Energy voluntarily notified state agencies and reported the leak of tritium to the Nuclear Regulatory Commission soon after it was confirmed and that the leak of 400,000 gallons of radioactive water never reached a threshold that would have required public notification.
“This is something that we struggle with because there is such concern with anything that is nuclear,” said Victoria Mitlyng, a spokesperson with the Nuclear Regulatory Commission. “The concern is very, very understandable. That is why I want to make extra clear the fact that the public in Minnesota, the people, the community near the plant, was not and is not in danger.”
State officials said that while they knew of the leak in November, they waited to get more information before making a public announcement.
“We knew there was a presence of tritium in one monitoring well, however Xcel had not yet identified the source of the leak and its location,” Minnesota Pollution Control Agency spokesperson Michael Rafferty said Thursday. “Now that we have all the information about where the leak occurred, how much was released into groundwater and that contaminated groundwater had moved beyond the original location, we are sharing this information.”
Tritium is a radioactive isotope of hydrogen that occurs naturally in the environment and is a common byproduct of nuclear plant operations. It emits a weak form of beta radiation that does not travel very far and cannot penetrate human skin, according to the Nuclear Regulatory Commission.
Edwin Lyman, director of nuclear power safety with the Union of Concerned Scientists, said a significant health risk would only occur if people consumed fairly high amounts of tritium. That risk is contained if the plume stays on the company’s site, which Xcel Energy and Minnesota officials said is the case.
If regulatory officials are sure it didn’t move off site, people shouldn’t have to worry about their safety, he said, adding that companies usually take action when onsite monitoring wells detect elevated levels of contaminants like tritium.
Mitlyng said there’s no official requirement for nuclear plants to report all tritium leaks to the Nuclear Regulatory Commission. Instead, Xcel Energy had previously agreed to report certain tritium leaks to the state. When Xcel Energy shares information with the state, it also shares it with the commission.
The commission posted a notification about the leak on its website Nov. 23, noting that the plant reported it to the state a day earlier. The report classified the leak as a nonemergency. The notice said the source of the tritium was being investigated at that time.
Beyond that, there was no widespread notification to the public before Thursday.